Bandwidth Limit Exceeded: Causes and How to Resolve them

Bandwidth Limit Exceeded: Causes and How to Resolve them

Have you encountered the dreaded “509 Bandwidth Limit Exceeded” error? If you have, you understand the frustration it brings to users. However, for website owners, this error poses an even greater challenge, potentially leading to the loss of valuable customers.

But what exactly is the 509 Bandwidth Limit Exceeded error, and how can you address it or, better yet, prevent it entirely?

Read this detailed guide to find all the answers.

What Is 509 Bandwidth Limit Exceeded Error?

As evident from the name, this error occurs when your website exceeds its monthly bandwidth quota provided by your web hosting provider.

As you are already aware, bandwidth refers to the volume of data that can be sent back and forth between websites and visitors. You will be assigned a monthly bandwidth quota in gigabytes (GB) when you select a web hosting package.

Your website’s performance and speed may suffer with low bandwidth. So, you need to make sure your plan has sufficient bandwidth.
Still, if your website exceeds that limit, your site visitors will see the following message:

Bandwidth limit exceeded error Source

This means that your site visitors won’t be able to interact with your website or consume content. This is a lost opportunity for your business, one that you must avoid at all costs.

We’ll discuss ways to resolve and avoid this later. First, let’s understand what causes the bandwidth limit exceeded error.

What Causes the 509 Bandwidth Limit Exceeded Error? 

Before you can learn how to prevent the 509 bandwidth limit exceeded error, you must understand what causes it.

This will help you understand exactly what to avoid, so let’s discuss the common causes of this error.

Here you go:

1.  Sudden Spikes in Web Traffic

Even if you have sufficient bandwidth for your average website traffic, sudden spikes in traffic can cause this error. While getting more traffic is beneficial, sudden, unexpected spikes can throw things off balance.

The solution?

Keep a good margin, and always opt for a plan with more bandwidth than you normally need. Remember, you want more web traffic, and skimping on a hosting plan is not good for your business.

2.  Publishing Media-Heavy Content

If you publish large images or video content on your website, it can consume a lot of bandwidth every time such files load. The best way to solve this problem is to compress your media files before uploading them. This way, they’ll consume less bandwidth and load faster.

3.  Poor Website Optimization

If your website has inefficient code or a theme that consumes more bandwidth, then that can throw off your bandwidth calculation and cause this error.

Using a light theme and regularly monitoring and optimizing your site code can help. So regularly monitor your site’s metrics and adjust your optimization strategies accordingly to contribute to a smoother and more reliable online experience for your visitors.

4.  Hotlinking and External Embeds

When other sites link directly to content or media on your site, it can consume a lot of bandwidth and cause the “509 bandwidth limit exceeded” error. 

As this consumes bandwidth without your permission, you will likely be blindsided unless you take precautionary measures. We’ll discuss those in detail in later sections.

5.  Insufficient Hosting Resources

One of the most common causes of the bandwidth limit exceeded error is that your hosting simply doesn’t have enough bandwidth. This happens if you inaccurately assess your bandwidth requirements and opt for a lower-tier plan.

That’s why it’s important to choose the right web hosting plan right from the start instead of facing errors and upgrading it later.

6.  Bot Traffic or DDoS Attacks

Sometimes, malicious bots can flood your website with requests, consuming a lot of bandwidth. A Distributed Denial of Service (DDoS) attack is another reason why your website’s bandwidth could cross the allocated limit.

The image below shows how such attacks affect a website and cause its bandwidth limit to exceed.

How bot attacks cause bandwidth limit exceeded errorSource

Using good security measures can help you prevent such attacks. In later sections, we’ll discuss the security measures you can take in detail.

7.  Using Shared Hosting

Shared hosting is a web hosting model where two or more sites use the same server. It’s an effective way for new websites to get started without paying too much for web hosting.

The problem arises when one of the other websites consumes a lot more bandwidth than expected. This could cause a bandwidth limit exceeded error for all websites using the server.

The simplest way to avoid this is to use VPS hosting or dedicated hosting.

VPS hosting involves splitting a server into various private servers to provide dedicated resources to users on each server. This means that other websites on the server won’t consume the bandwidth allocated to you.

Dedicated hosting, as the name suggests, involves hosting only one website on one server.

Here’s an image that illustrates the three types of hosting.

Shared, dedicated, and VPS hosting.

However, VPS and dedicated hosting plans are more expensive than shared hosting.

Irrespective of the hosting plan, you still need to follow certain best practices to avoid overloading your website or causing unnecessary bandwidth consumption.

We’ll discuss these best practices later in this article, but first, let’s understand the implication of the bandwidth limit exceeding error.

How Does the Bandwidth Limit Exceeded Error Affect SEO? 

When a website faces the 509 bandwidth limit exceeded error, it either works slowly or stops working altogether.

This negatively affects the user experience, which is one of the most important ranking factors for search engines.

Imagine this:

A user visits your website and finds it extremely slow to load. They immediately leave your website and visit a competitor’s website. 

This is a lost opportunity for your business. Not to mention, Google will see this as a signal that your website is either not relevant or provides a poor user experience, which will lower your SERP rankings.

Additionally, if your account is suspended and your website remains inactive for a while, then that will further affect your search rankings.

So, what’s the solution?

Fix a 509 error as soon as you see it to ensure there are no lasting SEO consequences. Read on to learn how.

What to Do If You Have a Bandwidth Limit Exceeded Error?

The first thing you need to do when you see the bandwidth limit exceeded error is to contact your hosting services provider.

Based on your unique requirements, you may need to take one of the following next steps:

  • Upgrade to a high-tier plan with more bandwidth allocation. This is ideal if you anticipate higher monthly traffic on an ongoing basis.
  • Ask your hosting provider to allocate additional bandwidth just for one month at an additional cost. This is a quick fix to ensure your site’s working as intended without increasing your monthly web hosting costs. It’s an ideal solution if there is an unexpected spike in traffic, which is not likely to happen again.

While these are reactive solutions to fix the problem immediately, it’s better to learn how to avoid the problem altogether. Find out how in the next section.

7 Ways to Avoid the 509 Bandwidth Limit Exceeded Error

“Prevention is better than cure”, is an adage that’s applicable in more situations than one, including this one.

The consequences of having a bandwidth limit exceeded error can be dire, so it’s better to ensure that it doesn’t occur.

Here are some best practices you can follow to avoid this error.

1. Choose the Right Hosting Plan and Service Provider

The simplest way to avoid the 509 bandwidth limit exceeded error is to choose the right hosting provider and plan.

This involves:

  • Researching and comparing various web hosting providers
  • Choosing a reputable one that has high ratings and provides the best plans for your needs
  • Calculating the bandwidth requirement for your website
  • Choosing a plan that not only meets your requirements but has sufficient bandwidth to handle unexpected traffic spikes

The trickiest part of this process is assessing your website’s bandwidth requirements. Let’s discuss that briefly.

How to Calculate Bandwidth Requirement

Here are four things calculations you need to make:

  • APS: The average page size of your web pages in KB
  • ANMV: The average number of monthly visitors
  • ANPV: The average number of page views per visitor

To estimate your bandwidth requirement, use this formula:

Bandwidth required = APS * ANMV * ANPV

Given that all the numbers included are estimates, this is a rough figure at best. That’s why it’s important to allocate extra bandwidth to handle traffic spikes and other situations that cause the bandwidth limit exceeded error.

As a general rule, add 50% of the number you calculated as the extra bandwidth allocation.

Other Considerations for Choosing a Hosting Plan

Even though you have a rough idea of how much bandwidth you need, your chosen hosting provider may not offer plans that meet your exact requirements.

In case you need to choose between two options, always go for the higher-tier plan with more bandwidth allocation. Also, note that some hosting providers offer unlimited bandwidth but have hidden usage restrictions. So, make sure you do your due diligence and understand the plans and pricing well before you choose one.

BigRock, for example, offers unmetered hosting and clearly discloses its fair use policy. It clearly states the terms and conditions, and there are no hidden costs or charges.

BigRock unmetered hosting policySource

2. Use a Content Delivery Network (CDN) and Caching

If your web traffic comes from various geographical regions, using a content delivery network (CDN) is a great idea.

It is a model that reduces the load on the main server by sharing it with multiple regional servers.

Here’s an image that perfectly illustrates and explains the concept.

Content Delivery Network illustrationSource

You should also use CDN caching to improve your page load times.

It allows you to store static files on regional CDN servers and deliver them to customers directly from there. This allows your web pages to load faster and reduces the load on your main server.

Some web hosting providers offer free CDNs with their hosting plans. BigRock, for instance, offers built-in Cloudflare CDN with its web hosting plans.

Using a CDN ensures that there’s not a lot of load on one server and that your website’s bandwidth does not exceed the allocated quota.

Apart from this, there are two other strategies you can use:

  • Use browser caching to store some recently used data in the visitor’s browser instead of storing it on your server. This quickens the loading of pages and uses less bandwidth.
  • Use the lazy-loading technique to ensure that media files on your web pages are loaded only when a user scrolls through to reach that part of a web page. This means the entire web page isn’t loaded instantly but as needed. This avoids unnecessary bandwidth use in case users leave a web page without reading till the end.

This image by Google explains how Lazy Loading can help reduce the amount of bandwidth consumed.

Lazy Loading technique


3. Optimize Your Website Files and Database

The files stored on your website take up a lot of space and consume a significant share of your monthly bandwidth quota.
Poor file storage and database management can lead to more bandwidth consumption than necessary.

The first thing you should do is compress large files stored on your website. These are typically image or video files. You can use image and video compression tools to compress large files before uploading them to the database.

Using the Webp image format instead of PNG or JPG is another great way to optimize your image file sizes.

There are numerous paid and free tools and plugins you can use for image compression. TinyPNG is one such tool that offers both free and paid plans.

TinyPng homepage banner imageSource

Another thing you can do is use light themes for your website that do not consume a lot of bandwidth. Make sure the theme you choose is mobile-responsive and renders well on all devices. A heavy, complex theme won’t be good for mobile use, so avoid those.

4. Delete Any Unused Files and Plugins

Next, you should delete duplicate, unused, or unnecessary files and clean your database. This will further reduce unnecessary bandwidth consumption. This includes unused themes or plugins that are just taking up space and consuming bandwidth but not solving any purpose.

Make sure you do a thorough review of your database and remove all files that are not needed. Conduct such reviews regularly to keep your database clean and optimized.

You’ll need to use a File Transfer Protocol (FTP) or file manager to connect with your server and delete unwanted files. Plugins and themes you can delete directly from your website.

5. Prepare for Traffic Spikes

No matter what the cause of the increase in traffic, your website should be prepared to handle unexpected traffic spikes. This is because no matter how many prevention measures you take, some things will slip through the cracks and cause problems anyway. That’s why it’s better to be prepared. But how can you do that?

The simplest way to do this is to pay for and keep more bandwidth than you need. In general, keeping 50% extra bandwidth than your average monthly requirement should be good enough to prevent your bandwidth limit from being exceeded.

Another option is to choose a hosting service provider that offers scalable plans and will inform you of the possibility of limit exceeding before it happens. They may contact you and offer deals on extra bandwidth for the month.
Plans that charge extra for extra bandwidth are also great, as long as the charges are nominal and you’re informed in advance.

Pro Tip: You should set up alerts and notifications for yourself when the bandwidth limit has reached a critical point and is about to be breached. This will give you enough time to take action and avoid the 509 error.

6. Increase Site Security and Prevent Hotlinking

Two common causes of bandwidth limit exceeding are hotlinking and bot or DDoS attacks. Putting security measures in place can help in both cases.

Let’s discuss the security measures you can take for each.

Here are a few tips to help you improve your site’s security measures and avoid bot or DDoS attacks:

  • Use a good firewall to restrict unwanted or malicious bot traffic from accessing your website. A good firewall can also restrict or block traffic from certain locations or IP addresses.
  • Invest in security services that offer real-time threat monitoring to detect and prevent such attacks quickly.
  • Use rate limiting to limit the traffic volume your website can receive during a given time period.
  • Use cloud-based DDoS mitigation services to prevent DDoS attacks on your website.

Using a good security service and firewall can take care of all aspects of site security. As such, do your research to find and invest in the best security services and solutions to secure your website from all digital threats.

How to Prevent Hotlinking?

As previously mentioned, hotlinking is a practice where other sites link to a resource on yours, such as a media file. This directs traffic to your website that consumes bandwidth without any benefit to you.

This is not the same as backlinking, where you intentionally want referral traffic from an authoritative site to yours. That’s beneficial for SEO, but hotlinking is not because it directs traffic to files (instead of useful pages) and is done without your consent.

Here’s an image that explains the concept.

What is hotlinkingSource

Luckily for you, there are many ways to prevent hotlinking, let’s discuss some of them.

  • Invest in a CDN that provides built-in hotlink prevention to simplify things for yourself.
  • Add a code to your .htaccess file that prevents hotlinking.
  • Use WordPress security and firewall plugins that offer this feature if your site is hosted on the platform.
  • Delete or rename the hot-linked files to cut access.
  • Disable right-click on images to prevent image hotlinking, which is the most common kind of hotlinking.
  • Block IP addresses that are known to hotlink to your website.
  • Enable cPanel hotlink protection, which stops other websites from embedding your content or files on theirs.

7. Monitor Your Website Regularly

Despite using all the prevention measures mentioned above, there can still be slips and misses. That’s why it’s a good practice to monitor your website performance, traffic, and bandwidth use regularly.

Use web analytics tools like Google Analytics to track your site’s traffic patterns and flag instances of traffic spikes. Find the causes of such spikes and take appropriate action. This could include blocking IP addresses that need to be blocked, updating site security, or anything else, depending on the cause of spikes.

If you see a consistent increase in your monthly traffic, consider updating your hosting plan and opt for one that can handle the increased bandwidth usage.
Regular monitoring and analysis will help you stay on top of things and not be blindsided by a 509 bandwidth exceeded error.


The bandwidth limit exceeded error is an inconvenience at best and highly detrimental to your website’s SEO at worst.

In any case, it can’t be left unchecked. In fact, it’s better to prevent it from happening instead of taking reactive measures to fix the problem.

Use the prevention measures listed in this post to avoid this error. Here are some key tips:

  • Assess your bandwidth requirement accurately and choose the right hosting plan.
  • Use a content delivery network and caching and lazy loading techniques to avoid overloading your website server.
  • Compress large files on your website, and delete any unused files or plugins.
  • Invest in site security measures and services to prevent bot attacks, hotlinking, and other malicious practices.

Looking for a trustworthy hosting services provider with generous plans? Check out the web hosting services offered by BigRock. It has an unmetered, unlimited bandwidth option, which can help you avoid the bandwidth limit exceeded error.


Web hosting specialist with a knack for creativity and a passion for baking, serving up tech solutions with a side of sweetness.